The listing, Two First Day Covers - Honoring America's Inventors - 1983 has ended.
Two first day covers - Honoring America's Inventors
(The grey you see in the picture is shadow - sorry, I don't have good lighting for pictures)
Honoring Nikola Tesla (electric induction motor) and Philo T Farnsworth (pioneer in television) - with a stamp for each - date of issue 21 Sep 1983, postmarked in Washington, D.C
Honoring Charles Steinmetz (pioneer in electricity) and Edwin Armstrong (FM radio) - with a stamp for each - date of issue 21 Sep 1983, postmarked in Washington, D.C.